Light emitting device and lighting system

ABSTRACT

A light emitting device may be provided that includes a conductive support member; a first conductive layer disposed on the conductive support member; a second conductive layer disposed on the first conductive layer; a light emitting structure including a second semiconductor layer formed on the second conductive layer, an active layer formed on the second semiconductor layer, a first semiconductor layer formed on the active layer and an insulation layer. The first conductive layer includes at least one via penetrating the second conductive layer, the second semiconductor layer and the active layer and projecting into a certain area of the first semiconductor layer. The first semiconductor layer includes an ohmic contact layer formed on or above the conductive via. The insulation layer is formed between the first conductive layer and the second conductive layer and is formed on the side wall of the via.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119(e) ofKorean Patent Application No. 10-2010-0097280 filed on Oct. 6, 2010,which is hereby incorporated by reference in its entirety.

BACKGROUND

1. Field

The present invention relates to a light emitting device and a lightingsystem.

2. Background

A light emitting diode (LED) is a semiconductor element for convertingelectric energy into light. As compared with existing light sources suchas a fluorescent lamp and an incandescent electric lamp and so on, theLED has advantages of low power consumption, a semi-permanent span oflife, a rapid response speed, safety and an environment-friendliness.For this reason, many researches are devoted to substitution of theexisting light sources with the LED. The LED is now increasingly used asa light source for lighting devices, for example, various lamps usedinteriorly and exteriorly, a liquid crystal display device, an electricsign and a street lamp and the like.

FIGS. 1 and 2 are cross sectional views showing the schematicconfigurations of prior vertical type light emitting devices.

First, referring to FIG. 1, a prior light emitting device 100 includes asubstrate 110, a p-type conductive layer 120, a p-type semiconductorlayer 130, an active layer 140, an n-type semiconductor layer 150 and ann-type electrode pad 160.

Regarding the light emitting device 100 shown in FIG. 1, light which isgenerated from the active layer 140 and is outward emitted is partiallyblocked by the uppermost n-type electrode pad 160. Therefore, the lightemitting device 100 has low light emission efficiency.

Next, referring to FIG. 2, a prior light emitting device 200 includes asubstrate 210, an n-type conductive layer 220, an insulation layer 230,a p-type conductive layer 240, a p-type semiconductor layer 250, anactive layer 260, an n-type semiconductor layer 270 and an n-typeelectrode pad 241. The n-type conductive layer 220 includes conductivevias 220 a, 220 b and 220 c penetrating the p-type conductive layer 240,the p-type semiconductor layer 250 and the active layer 260 andcontacting with the n-type semiconductor layer 270.

Unlike the light emitting device 100 shown in FIG. 1, the upper portionof the light emitting device 200 shown in FIG. 2 is not blocked by anelectrode, so that the light emitting device 200 has light-extractionefficiency higher than that of a prior light emitting device.

However, the insulation layer 230 is formed in the areas of theconductive vias 220 a, 220 b and 220 c, which project into the n-typesemiconductor layer 270. This causes a contact area between the n-typeconductive layer 220 and the n-type semiconductor layer 270 to bedecreased. The sloping surfaces of the conductive vias 220 a, 220 b and220 c increase with the increases of the depths of the conductive vias220 a, 220 b and 220 c, so that a contact area between the n-typesemiconductor layer 270 and the conductive vias 220 a, 220 b and 220 cis reduced. For this reason, the prior light emitting device having avia electrode shape has limited light-extraction efficiency.

SUMMARY

One embodiment is a light emitting device. The light emitting deviceincludes: a conductive support member; a first conductive layer disposedon the conductive support member; a second conductive layer disposed onthe first conductive layer; a light emitting structure including a firstsemiconductor layer placed over the second conductive layer, a secondsemiconductor layer placed between the first semiconductor layer and thesecond conductive layer and an active layer placed between the firstsemiconductor layer and the second semiconductor layer; and aninsulation layer placed between the first conductive layer and thesecond conductive layer. The first conductive layer may include at leastone via which penetrates the second conductive layer, the secondsemiconductor layer and the active layer and is disposed within thefirst semiconductor layer. The insulation layer may be disposed toextend along the side of the via. The first semiconductor layer mayinclude an ohmic contact layer formed on or above the conductive via.

According to the embodiment, the ohmic contact layer may be an Al dopedlayer.

The ohmic contact layer may be an AlGaN layer.

BRIEF DESCRIPTION OF THE DRAWINGS

Arrangements and embodiments may be described in detail with referenceto the following drawings in which like reference numerals refer to likeelements and wherein:

FIGS. 1 and 2 are cross sectional views showing the schematicconfigurations of prior vertical light emitting devices.

FIG. 3 a is a view showing a top surface of a light emitting deviceaccording to a first embodiment of the present invention.

FIGS. 3 b and 3 c are cross sectional views schematically showing aconfiguration of the light emitting device according to a firstembodiment of the present invention.

FIGS. 4 a and 4 b are cross sectional views schematically showing aconfiguration of a light emitting device according to a secondembodiment of the present invention.

FIG. 5 is a view schematically showing a light emitting device package.

FIG. 6 is a view schematically showing a lighting device.

DETAILED DESCRIPTION

A thickness or a size of each layer may be magnified, omitted orschematically shown for the purpose of convenience and clearness ofdescription. The size of each component may not necessarily mean itsactual size.

It should be understood that when an element is referred to as being‘on’ or “under” another element, it may be directly on/under theelement, and/or one or more intervening elements may also be present.When an element is referred to as being ‘on’ or ‘under’, ‘under theelement’ as well as ‘on the element’ may be included based on theelement.

An embodiment may be described in detail with reference to theaccompanying drawings.

First Embodiment

FIG. 3 a is a view showing a top surface of a light emitting device 300according to a first embodiment of the present invention.

FIGS. 3 b and 3 c are cross sectional views schematically showingconfigurations of light emitting devices 300 a and 300 b according to afirst embodiment of the present invention. FIGS. 3 b and 3 c are crosssectional views of the light emitting devices 300 a and 300 b takenalong line A-A′ of FIG. 3 a.

First, referring to FIGS. 3 b and 3 c, the light emitting devices 300 aand 300 b according to the first embodiment of the present inventioninclude a conductive support member 310, a first conductive layer 320, asecond conductive layer 330, a light emitting structure including afirst semiconductor layer 340 placed over the second conductive layer330, a second semiconductor layer 350 placed between the firstsemiconductor layer 340 and the second conductive layer 330 and anactive layer 360 placed between the first semiconductor layer 340 andthe second semiconductor layer 350, an electrode pad 331 a, Al dopinglayers 341 a and 341 b, an insulation layer 370 and a passivation layer380.

Hereafter, for convenience of description, it is assumed that the firstconductive layer 320 is an n-type conductive layer, the secondconductive layer 330 is a p-type conductive layer, the electrode pad 331a is a p-type electrode pad, the first semiconductor layer 340 is ann-type semiconductor layer, and the second semiconductor layer 350 is ap-type semiconductor layer.

The conductive support member 310 may be formed including at least oneof Au, Ni, Al, Cu, W, Si, Se and GaAs. For example, the conductivesupport member 310 may be made of a metal alloy of Si and Al.

The n-type conductive layer 320 may include a conductive layer formed onthe conductive support member 310, and a plurality of conductive vias320 a connected with each other by the conductive layer. The n-typeconductive layer 320 may be formed including at least one of Ag, Al, Au,Pt, Ti, Cr and W.

As shown in FIGS. 3 b and 3 c, the conductive via 320 a may be formed topenetrate the n-type conductive layer 320, the p-type conductive layer330, the p-type semiconductor layer 350 and the active layer 360, and toproject into a certain area of the n-type semiconductor layer 340.

The insulation layer 370 may be formed such that the n-type conductivelayer 320 is electrically insulated from the layers except for theconductive support member 310 and the n-type semiconductor layer 340.More specifically, the insulation layer 370 is formed between the n-typeconductive layer 320 and the p-type conductive layer 330 and formed onthe side walls of the plurality of conductive vias 320 a, so that then-type conductive layer 320 can be electrically insulated from thep-type conductive layer 330, the p-type semiconductor layer 350 and theactive layer 360. The insulation layer 370 may be formed including atleast one of silicon oxide (SiO₂), silicon nitride (SiO_(x)N_(y),Si_(x)N_(y)), Al₂O₃ and fluoride based compound.

The p-type conductive layer 330 may be formed on the insulation layer370. The p-type conductive layer 330 does not exist in the areas whichthe conductive via 320 a penetrates.

The p-type conductive layer 330 may include at least one of indium tinoxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO),indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO),indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tinoxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, RuOx/ITO, Ni/IrOx/Au,and Ni/IrOx/Au/ITO, Pt, Ni, Au, Rh, Pd, Ag, Al, Ir. This intends tominimize the contact resistance of the p-type semiconductor layer 350because the p-type conductive layer 330 electrically contacts with thep-type semiconductor layer 350. This also intends to improve lightemission efficiency by reflecting outward light generated from theactive layer 360.

The p-type conductive layer 330 may include at least one exposed area331 of the interface on which the p-type conductive layer 330 contactswith the p-type semiconductor layer 350. On the exposed area, the p-typeelectrode pad 331 a may be formed in order to connect an external powersupply to the p-type conductive layer 330. On the exposed area 331, thep-type semiconductor layer 350, the active layer 360 and the n-typesemiconductor layer 340 are not formed. The p-type electrode pad 331 amay be formed in the corners of the light emitting devices 300 a and 300b. This intends to maximize the light emitting areas of the lightemitting devices 300 a and 300 b.

The p-type semiconductor layer 350 may be formed on the p-typeconductive layer 330. The active layer 360 may be formed on the p-typesemiconductor layer 350. The n-type semiconductor layer 340 may beformed on the active layer 360. The p-type semiconductor layer 350 andthe active layer 360 do not exist in the areas which the conductive via320 a penetrates.

The n-type semiconductor layer 340 may be formed of a semiconductormaterial having an empirical formula of In_(x)Al_(y)Ga_((1-x-y))N(0≦x≦1, 0≦y≦1, 0≦x+y≦1), for example, InAlGaN, GaN, AlGaN, InGaN, AlInN,AlN and InN and the like. An n-type dopant such as Si, Ge and Sn and thelike may be doped in the n-type semiconductor layer 340.

The n-type semiconductor layer 340 may include the Al doping layers 341a and 341 b formed on the conductive via 320 a. The Al doping layer 341a is formed by doping an n-GaN semiconductor layer 340 with Al. When theamount of carrier (hole concentration) of the n-type semiconductor layer340 is 1×1017 cm⁻³, this affects carrier concentration increase due tothe Al doping and does not affect band gap. The Al doping layer 341 amay be designated as an ohmic contact layer.

The Al doping layer 341 a may be, as shown in FIG. 3 b, formed on thetop surface of the conductive via 320 a. Otherwise, the Al doping layer341 b may be, as shown in FIG. 3 c, formed above the conductive via 320a within the n-type semiconductor layer 340.

In order to improve ohmic characteristics of the top surface of theconductive via 320 a, there is a method of reducing the width of apotential barrier formed on a contact surface between metal constitutingthe conductive via 320 a and semiconductor constituting the n-typesemiconductor layer 340. When the width of the potential barrier isreduced by using a method of increasing doping concentration, contactresistance is decreased due to electron tunneling and ohmic contact canbe improved. As a result, the Al doping layers 341 a and 341 bconcentrate carriers on the top surface of the conductive via 320 a, sothat the electron tunneling occurs more easily and the ohmiccharacteristics can be enhanced.

In the embodiment, the Al doping layer may be formed by doping aspecific area of a GaN layer with Al material. An AlGaN layer to bedescribed later in another embodiment may be formed by mixing Al and GaNin a certain ratio.

Meanwhile, the Al doping layer 341 b is formed as shown in FIG. 3 b, thetop surface of the conductive via 320 a may come in direct contact withthe n-type semiconductor layer 340. Accordingly, the conductive supportmember 310 may be electrically connected with the n-type semiconductorlayer 340 through the conductive via 320 a. In this case, since then-type conductive layer 320 is electrically connected with theconductive support member 310 and the n-type semiconductor layer 340, itis recommended that the n-type conductive layer 320 be formed of amaterial having minimal contact resistance with the conductive supportmember 310 and the n-type semiconductor layer 340.

The p-type semiconductor layer 350 may be formed of a semiconductormaterial having an empirical formula of In_(x)Al_(y)Ga_((1-x-y))N(0≦x≦1, 0≦y≦1, 0≦x+y≦1), for example, InAlGaN, GaN, AlGaN, InGaN, AlInN,AlN and InN and the like. A p-type dopant such as Mg and Zn and the likemay be doped in the p-type semiconductor layer 350.

The active layer 360 may be formed of a semiconductor material having anempirical formula of In_(x)Al_(y)Ga_((1-x-y))N (0≦x≦1, 0≦y≦1, 0≦x≦y≦1).When the active layer 360 is formed in a multiple quantum well (MQW)structure, the active layer 360 may be formed by stacking a plurality ofwell layers and a plurality of barrier layers, for example, at a cycleof InGaN well layer/GaN barrier layer.

The active layer 360 may be formed of another material in accordancewith the materials constituting the n-type semiconductor layer 340 andthe p-type semiconductor layer 350. In other words, the active layer 360includes a layer which converts energy by the recombination of electronsand holes into light and emits the light. When the active layer 360includes the well layers and the barrier layers, it is recommended thatthe active layer 360 should be formed such that an energy band gap ofthe well layer is smaller than that of the barrier layer.

Meanwhile, the active layer 360 exposed outward may function as acurrent leakage path during the working of the light emitting devices300 a and 300 b. Here, such a problem is prevented by forming thepassivation layer 380 on the side wall of the light emitting structure.The passivation layer 380 protects the light emitting structure,especially the active layer 360 from the outside and restrains a leakagecurrent from flowing. The passivation layer 380 may be formed includingat least any one of silicon oxide (SiO₂), silicon nitride (SiO_(x)N_(y),Si_(x)N_(y)), metal oxide (Al₂O₃) and fluoride based compound.

Second Embodiment

FIGS. 4 a and 4 b are cross sectional views schematically showingconfigurations of light emitting devices 400 a and 400 b according to asecond embodiment of the present invention.

First, referring to FIGS. 4 a and 4 b, the light emitting devices 400 aand 400 b according to the second embodiment of the present inventioninclude a conductive support member 410, a first conductive layer 420, asecond conductive layer 430, a light emitting structure including afirst semiconductor layer 440 placed over the second conductive layer430, a second semiconductor layer 450 placed between the firstsemiconductor layer 440 and the second conductive layer 430 and anactive layer 460 placed between the first semiconductor layer 440 andthe second semiconductor layer 450, an electrode pad 431 a, AlGaN layers441 a and 441 b, an insulation layer 470 and a passivation layer 480.

Hereafter, for convenience of description, it is assumed that the firstconductive layer 420 is an n-type conductive layer, the secondconductive layer 430 is a p-type conductive layer, the electrode pad 431a is a p-type electrode pad, the first semiconductor layer 440 is ann-type semiconductor layer, and the second semiconductor layer 450 is ap-type semiconductor layer.

The conductive support member 410 may be formed including at least oneof Au, Ni, Al, Cu, W, Si, Se and GaAs. For example, the conductivesupport member 310 may be made of a metal alloy of Si and Al.

The n-type conductive layer 420 may include a conductive layer formed onthe conductive support member 410, and a plurality of conductive vias420 a connected with each other by the conductive layer. The n-typeconductive layer 420 may be formed including at least one of Ag, Al, Au,Pt, Ti, Cr and W.

As shown in FIGS. 4 a and 4 b, the conductive via 420 a may be formed topenetrate the n-type conductive layer 420, the p-type conductive layer430, the p-type semiconductor layer 450 and the active layer 460, and toproject into a certain area of the n-type semiconductor layer 440.

The insulation layer 470 may be formed such that the n-type conductivelayer 420 is electrically insulated from the layers except for theconductive support member 410 and the n-type semiconductor layer 440.More specifically, the insulation layer 470 is formed between the n-typeconductive layer 420 and the p-type conductive layer 430 and formed onthe side walls of the plurality of conductive vias 420 a, so that then-type conductive layer 420 can be electrically insulated from thep-type conductive layer 430, the p-type semiconductor layer 450 and theactive layer 460. The insulation layer 470 may be formed including atleast one of silicon oxide (SiO₂), silicon nitride (SiO_(x)N_(y),Si_(x)N_(y)), Al₂O₃ and fluoride based compound.

The p-type conductive layer 430 may be formed on the insulation layer470. The p-type conductive layer 430 does not exist in the areas whichthe conductive via 420 a penetrates.

The p-type conductive layer 430 may include at least one of indium tinoxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO),indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO),indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tinoxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, RuOX/ITO, Ni/IrOx/Au,and Ni/IrOx/Au/ITO, Pt, Ni, Au, Rh, Pd, Ag, Al, Ir. This intends tominimize the contact resistance of the p-type semiconductor layer 450because the p-type conductive layer 430 electrically contacts with thep-type semiconductor layer 450. This also intends to improve lightemission efficiency by reflecting outward light generated from theactive layer 460.

The p-type conductive layer 430 may include at least one exposed area431 of the interface on which the p-type conductive layer 430 contactswith the p-type semiconductor layer 450. On the exposed area, the p-typeelectrode pad 431 a may be formed in order to connect an external powersupply to the p-type conductive layer 430. On the exposed area 431, thep-type semiconductor layer 450, the active layer 460 and the n-typesemiconductor layer 440 are not formed. The p-type electrode pad 431 amay be formed in the corners of the light emitting devices 400 a and 400b. This intends to maximize the light emitting areas of the lightemitting devices 400 a and 400 b.

The p-type semiconductor layer 450 may be formed on the p-typeconductive layer 430. The active layer 460 may be formed on the p-typesemiconductor layer 450. The n-type semiconductor layer 440 may beformed on the active layer 460. The p-type semiconductor layer 450 andthe active layer 460 do not exist in the areas which the conductive via420 a penetrates.

The n-type semiconductor layer 440 may be formed of a semiconductormaterial having an empirical formula of In_(x)Al_(y)Ga_((1-x-y))N(0≦x≦1, 0≦y≦1, 0≦x+y≦1), for example, InAlGaN, GaN, AlGaN, InGaN, AlInN,AlN and InN and the like. An n-type dopant such as Si, Ge and Sn and thelike may be doped in the n-type semiconductor layer 340.

The n-type semiconductor layer 440 may include the AlGaN layers 441 aand 441 b formed on the conductive via 420 a. The AlGaN layer 441 a maybe, as shown in FIG. 4 a, formed on the top surface of the conductivevia 420 a. Otherwise, the AlGaN layer 441 b may be, as shown in FIG. 4b, formed above the conductive via 420 a within the n-type semiconductorlayer 440. The AlGaN layers 441 a and 441 b may be formed by growing acap layer on an n-GaN semiconductor layer 440. The AlGaN layers 441 aand 441 b have an empirical formula of Al_(x)Ga(1−x)N (0≦x≦1),influences a mole fraction of group III element in accordance with theamount of Al, and gives variety to band gap depending on the influence.The AlGaN layer 441 a may be designated as an ohmic contact layer.

The AlGaN layers 441 a and 441 b as a material, which belongs to thesame group as that of the n-GaN semiconductor layer 440 and has a bandgap different from that of the n-GaN semiconductor layer 440, reduce adepletion region between the conductive via 420 a and the n-GaNsemiconductor layer 440 or lower a surface Schottky barrier between theconductive via 420 a and the n-GaN semiconductor layer 440 by causingspontaneous polarization and piezoelectric polarization. As a result,ohmic characteristic can be improved.

Meanwhile, the AlGaN layer 441 a is formed as shown in FIG. 4 b, the topsurface of the conductive via 420 a may come in direct contact with then-type semiconductor layer 440. Accordingly, the conductive supportmember 410 may be electrically connected with the n-type semiconductorlayer 440 through the conductive via 420 a. In this case, since then-type conductive layer 420 is electrically connected with theconductive support member 410 and the n-type semiconductor layer 440, itis recommended that the n-type conductive layer 420 be formed of amaterial having minimal contact resistance with the conductive supportmember 410 and the n-type semiconductor layer 440.

The p-type semiconductor layer 450 may be formed of a semiconductormaterial having an empirical formula of In_(x)Al_(y)Ga_((1-x-y))N(0≦x≦1, 0≦y≦1, 0≦x+y≦1), for example, InAlGaN, GaN, AlGaN, InGaN, AlInN,AlN and InN and the like. A p-type dopant such as Mg and Zn and the likemay be doped in the p-type semiconductor layer 450.

The active layer 460 may be formed of a semiconductor material having anempirical formula of In_(x)Al_(y)Ga_((1-x-y))N (0≦x≦1, 0≦y≦1, 0≦x+y≦1).When the active layer 460 is formed in a multiple quantum well (MQW)structure, the active layer 460 may be formed by stacking a plurality ofwell layers and a plurality of barrier layers, for example, at a cycleof InGaN well layer/GaN barrier layer.

The active layer 460 may be formed of another material in accordancewith the materials constituting the n-type semiconductor layer 340 andthe p-type semiconductor layer 450. In other words, the active layer 460converts energy by the recombination of electrons and holes into lightand emits. Therefore, it is recommended that the active layer 460 beformed of a material having an energy band gap smaller than those of then-type semiconductor layer 440 and the p-type semiconductor layer 450.

Meanwhile, the active layer 460 exposed outward may function as acurrent leakage path during the working of the light emitting devices400 a and 400 b. Here, such a problem is prevented by forming thepassivation layer 480 on the side wall of the light emitting structure.The passivation layer 480 protects the light emitting structure,especially the active layer 460 from the outside and restrains a leakagecurrent from flowing. The passivation layer 480 may be formed includingat least any one of silicon oxide (SiO₂), silicon nitride (SiO_(x)N_(y),Si_(x)N_(y)), metal oxide (Al₂O₃) and fluoride based compound.

[Light Emitting Device Package]

Hereafter, a light emitting device package according to an embodimentwill be described with reference to FIG. 5. FIG. 5 is a cross sectionalview showing schematically a light emitting device package 1000.

As shown in FIG. 5, the light emitting device package 1000 according tothe embodiment includes a package body 1100, a first electrode layer1110, a second electrode 1120, a light emitting device 1200 and a filler1300.

The package body 1100 may be formed including a silicon material, asynthetic resin material or a metallic material. Inclined surfaces areformed around the light emitting device 1200, thereby improving thelight-extraction efficiency.

The first electrode layer 1110 and the second electrode 1120 aredisposed in the package body 1100. The first electrode layer 1110 andthe second electrode 1120 are electrically isolated from each other andsupply electric power to the light emitting device 1200. The firstelectrode layer 1110 and the second electrode 1120 are able to increaseluminous efficiency by reflecting light generated from the lightemitting device 1200. The first electrode layer 1110 and the secondelectrode 1120 can also exhaust heat generated from the light emittingdevice 1200.

The light emitting device 1200 is electrically connected to the firstelectrode layer 1110 and the second electrode 1120. The light emittingdevice 1200 may be disposed on the package body 1100 or may be disposedon either the first electrode layer 1110 or the second electrode 1120.

The light emitting device 1200 may be also electrically connected to thefirst electrode layer 1110 and the second electrode 1120 by any one of awire bonding manner, a flip-chip manner or a die-bonding process.

The filler 1300 may be formed to surround and protect the light emittingdevice 1200. The filler 1300 includes a fluorescent material, so thatthe wavelength of light emitted from the light emitting device 1200 maybe changed.

The light emitting device package 1000 is equipped with at least one ora plurality of the light emitting devices disclosed in the embodiments.There is no limited to the number of the light emitting devices.

A plurality of the light emitting device packages 1000 according to theembodiment may be arrayed on a substrate. An optical member such as alight guide plate, a prism sheet and a diffusion sheet and the like maybe disposed on the optical path of the light emitting device package1000. Such a light emitting device package 1000, the substrate and theoptical member are able to function as a light unit.

Another embodiment can be implemented by a display device, a pointingdevice and a lighting device and the like, all of which include thesemiconductor light emitting device or the light emitting device packagewhich has been described in the aforementioned embodiments. For example,the lighting device may include a lamp and a street lamp.

[Lighting Device]

FIG. 6 is a perspective view showing a lighting device 1500 includingthe light emitting device package shown in FIG. 4.

Referring to FIG. 6, the lighting device 1500 may include a case 1510, alight emitting module 1530 disposed on the case 1510, a cover 1550connected to the case 1510, and a connection terminal 1570 connected tothe case 1510 and supplied with an electric power from an external powersupply.

The case 1510 may be formed of a material having an excellent heatradiating characteristic, for example, a metal material or a resinmaterial.

The light emitting module 1530 may include a board 1531 and at least onelight emitting device package 1533 which is based on the embodiment andis mounted on the board 1531. The plurality of the light emitting devicepackages 1533 may be radially arranged apart from each other at apredetermined interval on the board 1531.

The board 1531 may be an insulating substrate on which a circuit patternhas been printed, and may include, for example, a printed circuit board(PCB), a metal core PCB, a flexible PCB, a ceramic PCB, an FR-4substrate, etc.

Also, the board 1531 may be formed of a material capable of efficientlyreflecting light. The surface of the board 1531 may have a color capableof efficiently reflecting light, such as white or silver.

The at least one light emitting device package 1533 may be disposed onthe board 1531. Each of the light emitting device packages 1533 mayinclude at least one light emitting diode (LED) chip. The LED chip mayinclude both a LED emitting red, green, blue or white light and a UV LEDemitting ultraviolet (UV).

The light emitting module 1530 may have various combinations of thelight emitting device packages so as to obtain desired color andluminance. For example, the light emitting module 1530 may have acombination of a white LED, a red LED and a green LED in order to obtaina high color rendering index (CRI).

The connection terminal 1570 may be electrically connected to the lightemitting module 1530 in order to supply power. The connection terminal1570 may be screwed and connected to an external power in the form of asocket. However, there is no limit to the method for connecting theconnection terminal 1570 to an external power. For example, theconnection terminal 1570 may be made in the form of a pin and insertedinto the external power, or may be connected to the external powerthrough a power line.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to affect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A light emitting device comprising: a conductivesupport member; a first conductive layer disposed on the conductivesupport member; a second conductive layer disposed on the firstconductive layer; a light emitting structure including a firstsemiconductor layer over the second conductive layer, a secondsemiconductor layer between the first semiconductor layer and the secondconductive layer and an active layer between the first semiconductorlayer and the second semiconductor layer; and an insulation layerbetween the first conductive layer and the second conductive layer,wherein the first conductive layer includes at least one via thatpenetrates the second conductive layer, the second semiconductor layerand the active layer, and the via is disposed within the firstsemiconductor layer, wherein the insulation layer is disposed to extendalong a side of the via, and wherein the first semiconductor layerincludes an ohmic contact layer formed on or above the via within thefirst semiconductor layer.
 2. The light emitting device of claim 1,wherein the ohmic contact layer is an Al doped layer.
 3. The lightemitting device of claim 1, wherein the ohmic contact layer is an AlGaNlayer.
 4. The light emitting device of claim 1, further comprising apassivation layer formed on a side wall of the light emitting structure.5. The light emitting device of claim 1, wherein the second conductivelayer comprises at least one exposed area of surface forming aninterface with the second semiconductor layer, and the light emittingdevice further comprises an electrode pad formed on the exposed area ofthe second conductive layer.
 6. The light emitting device of claim 1,wherein the conductive support member comprises at least one of Au, Ni,Al, Cu, W, Si, Se and GaAs.
 7. The light emitting device of claim 1,wherein the first conductive layer comprises at least one of Ag, Al, Au,Pt, Ti, Cr and W.
 8. The light emitting device of claim 1, wherein thesecond conductive layer comprises at least one of Ag, Al, Pt, Ni, Pt,Pd, Au, Ir and a transparent conductive oxide, and wherein thetransparent conductive oxide comprises at least one of ITO and GZO. 9.The light emitting device of claim 1, wherein an area of a top surfaceof the via is less than an area of a bottom surface of the via.
 10. Thelight emitting device of claim 4, wherein the insulation layer and thepassivation layer are respectively formed including at least any one ofsilicon oxide, silicon nitride, metal oxide and fluoride based compound.11. The light emitting device of claim 1, wherein the active layer isformed by stacking a plurality of well layers and a plurality of barrierlayers.
 12. A light emitting device package comprising: a package body;a first electrode layer and a second electrode layer, all of which aredisposed on the package body; and the light emitting device of claim 1,the light emitting device being electrically connected to the firstelectrode layer and the second electrode layer.
 13. A lighting devicecomprising: a case; a light emitting module disposed within the case;and a connection terminal disposed within the case and electricallyconnected to the light emitting module in such a manner as to besupplied with an electric power from an external power supply, whereinthe light emitting module includes the light emitting device package ofclaim
 12. 14. A light emitting device comprising: a conductive supportmember; a first conductive layer on the conductive support member; asecond conductive layer on the first conductive layer, wherein thesecond conductive layer includes an exposed area; a light emittingstructure that includes a first semiconductor layer on the secondconductive layer, a second semiconductor layer between the firstsemiconductor layer and the second conductive layer and an active layerbetween the first semiconductor layer and the second semiconductorlayer; and an insulation layer between the first conductive layer andthe second conductive layer, wherein the first conductive layer includesat least one via provided in the first semiconductor layer and thatextends through the second conductive layer, the second semiconductorlayer and the active layer, wherein a top area of the via within thefirst semiconductor layer is less than a bottom area of the via at thesecond conductive layer, wherein the insulation layer is provided alonga side of the via, and wherein the first semiconductor layer includes anohmic contact layer formed on the top area of the via provided withinthe first semiconductor layer.
 15. The light emitting device of claim14, wherein the ohmic contact layer is an Al doped layer.
 16. The lightemitting device of claim 14, wherein the ohmic contact layer is an AlGaNlayer.
 17. The light emitting device of claim 14, further comprising apassivation layer on a side wall of the light emitting structure.
 18. Alight emitting device package comprising: a package body; a firstelectrode layer and a second electrode layer on the package body; andthe light emitting device of claim 14, wherein the light emitting deviceis electrically connected to the first electrode layer and the secondelectrode layer.
 19. A lighting device comprising: a case; a lightemitting module within the case; and a connection terminal within thecase and being electrically connected to the light emitting module to besupplied with an electric power from an external power supply, whereinthe light emitting module includes the light emitting device package ofclaim 18.